XPOT
Description
The XPOT (exportin for tRNA) is a protein-coding gene located on chromosome 12.
XPOT is a protein encoded by the XPOT gene in humans. It belongs to the RAN-GTPase exportin family and is responsible for exporting tRNA from the nucleus to the cytoplasm.
XPOT mediates the export of aminoacylated tRNAs from the nucleus to the cytoplasm. In the nucleus, it binds to tRNA and the GTPase Ran in its active GTP-bound form. This trimeric complex then docks to the nuclear pore complex (NPC) by interacting with nucleoporins. Once the complex enters the cytoplasm, it disassembles. This disassembly is triggered by the hydrolysis of Ran-GTP to Ran-GDP, facilitated by RANBP1 and RANGAP1, leading to the release of tRNA from XPOT. XPOT then returns to the nucleus to mediate another round of transport. The directionality of this process is likely determined by the uneven distribution of GTP- and GDP-bound forms of Ran between the cytoplasm and nucleus.
XPOT is also known as XPO3.
